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Aluminium Lower Unit Repair

I get the fins from Mercury Performance out of Florida. You would think they would be finished better for what they charge but the unit is a little rough when received.

The Customer is a true crusader on abuse of a product to its full potential.

Welded with my Signature Series DX 300 (thanks to Kevin (KB FAB)for a great unit)

At least he gave me the lower unit minus the BOAT

A question for the Forum- I was told the Yamaha motors and the Hondas have a different Aluminium blend and cannot be welded. Something to do with a mixture of Magnesium in the Aluminum.
Anyone know the truth on this?

I get the fins from Mercury Performance out of Florida. You would think they would be finished better for what they charge but the unit is a little rough when received.

The Customer is a true crusader on abuse of a product to its full potential.

Welded with my Signature Series DX 300 (thanks to Kevin (KB FAB)for a great unit)

At least he gave me the lower unit minus the BOAT

A question for the Forum- I was told the Yamaha motors and the Hondas have a different Aluminium blend and cannot be welded. Something to do with a mixture of Magnesium in the Aluminum.
Anyone know the truth on this?

Its not magnesium, its copper. And yes it can be welded. However I personally think any Yamaha or Honda should be scrapped anyway
If you want to weld on their castings use 4145 filler, preheat as you would normally for a cast material. Its nothing special, just cheap.

Comment

Since alum x-fers heat so rapidly, is the prop shaft seal left in place? Is the gear grease drained? Even if the grease is drained, what keeps the remaining grease from coking? Or is there enough mass to keep the heat dissipated?

TIA, Craig

RETIRED desk jockey.

Hobby weldor with a little training.

Craftsman O/A---Flat, Vert, Ovhd, Horz.

Miller Syncrowave 250.
sigpic

Comment

Since alum x-fers heat so rapidly, is the prop shaft seal left in place? Is the gear grease drained? Even if the grease is drained, what keeps the remaining grease from coking? Or is there enough mass to keep the heat dissipated?

TIA, Craig

Yes
No
NA
Yes
The front half of the weld is in a water port so no heat issues in this area.
The gear oil is Synthetic and the area that is exposed to heat is far enough away that a soaked rag is placed there to monitor and keep the temp in check. It never gets hot enough to steam, therfore less than 210 degrees.
Welding is done in 1" sections on opposite sides opposite directions to limit temp & any distortion potential, with time for cool down.

It is actually a fun repair as long as you are taking your time and have a good fit up. The bevel is a key component for the strength and if the customer does it again it will break on the edge.

Comment

Thanks for the descriptive answers. How many amps, or 'full' with pedal? I ask because: someone asked me to repair an alum radiator tonight in class. The 'welded in' nipple had five lengthwise cracks. Since it was only for a petcock, he asked me to fit the ID with a nickel sized plug, welding the nipple shut. And since the cracks were all around the perimeter, he also asked that I run another bead around the nipple itself (over the original nipple weld, which was too smalll to call a weld, no ripples, 1/16" radius).

The 1/8" thick nickel sized plug went well at 150 amps. But the outer weld would have nothing to do with 150. I ended up at 250 amps and that took 'scary' long, full pedal, to puddle. There was obiviously plenty of alum there, but I've never used that much heat (home hobby guy with an aircooled Sync 250). At class: Syncrowave 250, watercooled, 1/8" green (that's what the class supplies) 3/32" 4043.

I could only run 3/8 to 1/2" beads because of the small diameter (maybe 1 1/8" OD). And I used a wet rag to draw the heat away, NOT on the weld, just under steam temps. Lots of starts / stops 'cause I'm afraid of the disasterous melt through.

All this to ask: how many amps for the DX 300 on this repair? Sorry about the hijack.

Comment

I think most are intimidated as the learning curve is greater. It has become second nature over time. I will say that my stack is not as clean as KB or Engloid, as I was exposed to a smoother feed by my Teacher and really had never got the perfect stack. Mine is more like ripples than stacked. I can do it but I have to think about it.

I have a few customers that request a lower profile with very little height to the bead. I call it the "close call" as it is right there on the cusp of burn threw.
the bead profile is more on the inside than out when you do a test cut.

I can say also, I do not know it ALL, I am always learning, and I pick up more keeping an open mind than dictating. I have a lot of years under my belt and will be the first to say I have more to LEARN.

Fortunately I have good equipment, nice shop and a phone when I weld myself into a CORNER.

Comment

I too am learning to Tig Aluminum. It amazes me how demanding this process is! Like you La Weld I find I am more of a "rippler" I have yet figured out how to stack consistantly, and when I do I tend to run out of wire to feed and m y restarts mess up the consistancy. Does this have to do with using an inverter versus a transformer machine?? (just wondering or should I say hoping) LOL

I must say I have melted a lot of filler and burned up a lot of Argon! Congratulations Craig on making the radiator repair!! My first repair was a Snow shovel (hope not to have to use it again this year!!!

I will say that my stack is not as clean as KB or Engloid, as I was exposed to a smoother feed by my Teacher and really had never got the perfect stack. Mine is more like ripples than stacked. I can do it but I have to think about it.

With all due respect to KB and Engloid (I think they walk on 'welding' water); I don't care if my welds come out stacked or rippled, just as long as their cross section is consistant and they LOOK consistant. Sometimes dipping works, sometimes laywire works. And other times, nothing works.

I have a few customers that request a lower profile with very little height to the bead. I call it the "close call" as it is right there on the cusp of burn threw.
the bead profile is more on the inside than out when you do a test cut.

I can say also, I do not know it ALL, I am always learning, and I pick up more keeping an open mind than dictating. I have a lot of years under my belt and will be the first to say I have more to LEARN.

and when I do I tend to run out of wire to feed and my restarts mess up the consistancy.

I hope you're using 3/32" filler. I STILL don't 'get' 1/16". What I think I've learned about restarts: pull the filler away from the puddle. Do not try to restart. Now, restart the puddle, AND THEN, re-introduce the filler. Restarting the puddle, before re-introducing the filler has worked for me in both mild steel and alum.

After I plugged the nipple (first weld), I took the piece into my instructor to ask about the fusion between my bead and the base metal. He said it looked good and pointed out a pinhole. I said that I saw it and would catch it with my second, outer bead. Which I did. The only problem was: the instructor thought that I only needed to fix the pinhole. The outer bead was NO WHERE as pretty as the first and he told me so. =( But he hadn't see the lengthwise cracks, which would have propogated back to the surface. It's a good thing I'm THICK skinnned.

Comment

I hope us "ole" guys don't cause the youngen's to loose hope thinking they will be as old as us and still can't weld!! In truth with the help of a newly aquired friend that is a retired boilermaker/pipe welder I am gaining confidence daily! funny yesterday I ran a bunch of SS and he said they would no problem pass cert test (great encouragent to say the least) I then did some Mig beads (on your 252) that I haven't found a suitable box to ship it in) then ran a 1/8" fillet weld on AL and darned if it didn't look too bad!! (there is a God) and he held the torch today)

I will post a few progress photos as soon as I set up some "fresh coupons"

As for Gas $$$ I am just about to have to refill my 330cf as I am down to 500lbs!@!